Hexan-3-one can be obtained by the reaction of `EtMgBr` and.

Options

A. Butanamide
B. Propanamide
C. Butane nitrile
D. Propane nitrile

Explanation

To determine which compound can react with ethyl magnesium bromide (EtMgBr) to yield hexan-3-one, we need to analyze the reaction mechanism of Grignard reagents with carbonyl compounds and nitriles.

### Step-by-Step Solution:

1. **Identify the Structure of Hexan-3-one**:
Hexan-3-one is a ketone with the structure CH3-CO-CH2-CH2-CH3. The carbonyl group (C=O) is located at the third carbon in a six-carbon chain.

2. **Understand the Role of Grignard Reagents**:
Grignard reagents, such as EtMgBr, are nucleophiles that can attack electrophilic carbonyl carbon atoms. The ethyl group (C2H5-) from EtMgBr will add to the carbonyl carbon of a suitable electrophile.

3. **Consider Possible Electrophiles**:
To form hexan-3-one, we need a compound that can provide the necessary carbon skeleton. The options given are butanamide, propanamide, nitriles, and propanenitrile.

4. **Reacting with Butanamide**:
- Butanamide (CH3CH2CH2C(=O)NH2) has a carbonyl group that can react with EtMgBr.
- The reaction will yield an intermediate where the ethyl group attaches to the carbonyl carbon, resulting in a compound that can be hydrolyzed to form hexan-3-one.

5. **Hydrolysis of the Intermediate**:
- The intermediate formed after the reaction with butanamide will look like this: CH3CH2CH2C(OH)(C2H5)NH2.
- Upon hydrolysis, the amine group will be converted to an alcohol, and the product will be hexan-3-one (CH3-CO-CH2-CH2-CH3) along with ammonia and magnesium bromide byproducts.

6. **Conclusion**:
- The reaction of ethyl magnesium bromide with butanamide leads to the formation of hexan-3-one upon hydrolysis.
- Therefore, the answer to the question is **butanamide**.